feat(billboard): revise clearAuction(s) funcs to return prices and taxes

.gas-snapshot

@@ -10,17 +10,17 @@ ACLManagerTest:testRenounceRole() (gas: 27841)
 ACLManagerTest:testRoles() (gas: 15393)
 ACLManagerTest:testTransferRole() (gas: 21528)
 BillboardTest:testAddToWhitelist() (gas: 35114)
-BillboardTest:testApproveAndTransfer() (gas: 162534)
+BillboardTest:testApproveAndTransfer() (gas: 162468)
 BillboardTest:testCalculateTax() (gas: 21760)
-BillboardTest:testCannnotWithdrawTaxIfSmallAmount(uint8) (runs: 256, μ: 519125, ~: 524489)
-BillboardTest:testCannnotWithdrawTaxIfZero() (gas: 490314)
+BillboardTest:testCannnotWithdrawTaxIfSmallAmount(uint8) (runs: 256, μ: 519318, ~: 524555)
+BillboardTest:testCannnotWithdrawTaxIfZero() (gas: 490374)
 BillboardTest:testCannotAddToWhitelistByAttacker() (gas: 9037)
-BillboardTest:testCannotApproveByAttacker() (gas: 130326)
-BillboardTest:testCannotClearAuctionIfAuctionNotEnded() (gas: 699798)
-BillboardTest:testCannotClearAuctionOnNewBoard() (gas: 136208)
+BillboardTest:testCannotApproveByAttacker() (gas: 130281)
+BillboardTest:testCannotClearAuctionIfAuctionNotEnded() (gas: 700985)
+BillboardTest:testCannotClearAuctionOnNewBoard() (gas: 136261)
 BillboardTest:testCannotMintBoardByAttacker() (gas: 13321)
 BillboardTest:testCannotPlaceBidByAttacker() (gas: 246293)
-BillboardTest:testCannotPlaceBidTwice(uint96) (runs: 256, μ: 749648, ~: 754816)
+BillboardTest:testCannotPlaceBidTwice(uint96) (runs: 256, μ: 749802, ~: 754906)
 BillboardTest:testCannotRemoveToWhitelistByAttacker() (gas: 9104)
 BillboardTest:testCannotSafeTransferByAttacker() (gas: 127438)
 BillboardTest:testCannotSetBoardProprtiesByAttacker() (gas: 157292)
@@ -29,34 +29,34 @@ BillboardTest:testCannotSetTaxRateByAttacker() (gas: 9006)
 BillboardTest:testCannotTransferByOperator() (gas: 132771)
 BillboardTest:testCannotTransferToZeroAddress() (gas: 128258)
 BillboardTest:testCannotUpgradeRegistryByAttacker() (gas: 9128)
-BillboardTest:testCannotWithBidTwice(uint96) (runs: 256, μ: 1079596, ~: 1079596)
-BillboardTest:testCannotWithdrawBidIfAuctionNotCleared(uint96) (runs: 256, μ: 910976, ~: 910976)
-BillboardTest:testCannotWithdrawBidIfAuctionNotEnded(uint96) (runs: 256, μ: 725669, ~: 725669)
-BillboardTest:testCannotWithdrawBidIfNotFound() (gas: 427992)
-BillboardTest:testCannotWithdrawBidIfWon(uint96) (runs: 256, μ: 833971, ~: 833971)
+BillboardTest:testCannotWithBidTwice(uint96) (runs: 256, μ: 1079907, ~: 1079907)
+BillboardTest:testCannotWithdrawBidIfAuctionNotCleared(uint96) (runs: 256, μ: 911089, ~: 911089)
+BillboardTest:testCannotWithdrawBidIfAuctionNotEnded(uint96) (runs: 256, μ: 725782, ~: 725782)
+BillboardTest:testCannotWithdrawBidIfNotFound() (gas: 428052)
+BillboardTest:testCannotWithdrawBidIfWon(uint96) (runs: 256, μ: 834282, ~: 834282)
 BillboardTest:testCannotWithdrawTaxByAttacker() (gas: 16677)
-BillboardTest:testClearAuctionIfAuctionEnded() (gas: 743955)
-BillboardTest:testClearAuctionsIfAuctionEnded() (gas: 1376419)
-BillboardTest:testGetBids(uint8,uint8,uint8) (runs: 256, μ: 4688527, ~: 2075169)
+BillboardTest:testClearAuctionIfAuctionEnded(uint96) (runs: 256, μ: 837581, ~: 837581)
+BillboardTest:testClearAuctionsIfAuctionEnded() (gas: 1379962)
+BillboardTest:testGetBids(uint8,uint8,uint8) (runs: 256, μ: 4580822, ~: 2075259)
 BillboardTest:testGetTokenURI() (gas: 154936)
 BillboardTest:testMintBoard() (gas: 225541)
 BillboardTest:testMintBoardByWhitelist() (gas: 154942)
 BillboardTest:testMintBoardIfOpened() (gas: 145715)
-BillboardTest:testPlaceBidByWhitelist() (gas: 579119)
-BillboardTest:testPlaceBidIfAuctionEnded() (gas: 1090527)
-BillboardTest:testPlaceBidOnNewBoard(uint96) (runs: 256, μ: 619217, ~: 635029)
-BillboardTest:testPlaceBidWithHigherPrice(uint96) (runs: 256, μ: 905056, ~: 913141)
-BillboardTest:testPlaceBidWithSamePrices(uint96) (runs: 256, μ: 908042, ~: 917915)
-BillboardTest:testPlaceBidZeroPrice() (gas: 376887)
+BillboardTest:testPlaceBidByWhitelist() (gas: 579179)
+BillboardTest:testPlaceBidIfAuctionEnded() (gas: 1090700)
+BillboardTest:testPlaceBidOnNewBoard(uint96) (runs: 256, μ: 618577, ~: 635089)
+BillboardTest:testPlaceBidWithHigherPrice(uint96) (runs: 256, μ: 905402, ~: 913254)
+BillboardTest:testPlaceBidWithSamePrices(uint96) (runs: 256, μ: 908177, ~: 918050)
+BillboardTest:testPlaceBidZeroPrice() (gas: 376947)
 BillboardTest:testRemoveToWhitelist() (gas: 23188)
-BillboardTest:testSafeTransferByOperator() (gas: 141171)
+BillboardTest:testSafeTransferByOperator() (gas: 141193)
 BillboardTest:testSetBoardProperties() (gas: 305972)
 BillboardTest:testSetBoardPropertiesAfterTransfer() (gas: 335477)
 BillboardTest:testSetIsOpened() (gas: 22661)
 BillboardTest:testSetTaxRate() (gas: 22887)
-BillboardTest:testUpgradeRegistry() (gas: 3038450)
-BillboardTest:testWithdrawBid(uint96) (runs: 256, μ: 1081104, ~: 1081104)
-BillboardTest:testWithdrawTax(uint96) (runs: 256, μ: 597578, ~: 597578)
+BillboardTest:testUpgradeRegistry() (gas: 3131297)
+BillboardTest:testWithdrawBid(uint96) (runs: 256, μ: 1081415, ~: 1081415)
+BillboardTest:testWithdrawTax(uint96) (runs: 256, μ: 597638, ~: 597638)
 CurationTest:testCannotCurateERC20CurateZeroAmount() (gas: 12194)
 CurationTest:testCannotCurateERC20EmptyURI() (gas: 15797)
 CurationTest:testCannotCurateERC20IfNotApproval() (gas: 21624)

src/Billboard/Billboard.sol

@@ -142,7 +142,7 @@ contract Billboard is IBillboard {
     }
 
     /// @inheritdoc IBillboard
-    function clearAuction(uint256 tokenId_) public {
+    function clearAuction(uint256 tokenId_) public returns (uint256 price, uint256 tax) {
         // revert if board not found
         IBillboardRegistry.Board memory _board = registry.getBoard(tokenId_);
         require(_board.creator != address(0), "Board not found");
@@ -160,25 +160,37 @@ contract Billboard is IBillboard {
         address _prevOwner = registry.ownerOf(tokenId_);
         if (_nextAuction.startAt == 0 && _prevOwner != _board.creator) {
             registry.safeTransferByOperator(_prevOwner, _board.creator, tokenId_);
-            return;
+            return (0, 0);
         }
 
-        _clearAuction(tokenId_, _board.creator, _nextAuctionId);
+        return _clearAuction(tokenId_, _board.creator, _nextAuctionId);
     }
 
     /// @inheritdoc IBillboard
-    function clearAuctions(uint256[] calldata tokenIds_) external {
-        for (uint256 i = 0; i < tokenIds_.length; i++) {
-            clearAuction(tokenIds_[i]);
+    function clearAuctions(
+        uint256[] calldata tokenIds_
+    ) external returns (uint256[] memory prices, uint256[] memory taxes) {
+        uint256 _size = tokenIds_.length;
+        uint256[] memory _prices = new uint256[](_size);
+        uint256[] memory _taxes = new uint256[](_size);
+
+        for (uint256 i = 0; i < _size; i++) {
+            (_prices[i], _taxes[i]) = clearAuction(tokenIds_[i]);
         }
+
+        return (_prices, _taxes);
     }
 
-    function _clearAuction(uint256 tokenId_, address boardCreator_, uint256 nextAuctionId_) private {
+    function _clearAuction(
+        uint256 tokenId_,
+        address boardCreator_,
+        uint256 nextAuctionId_
+    ) private returns (uint256 price, uint256 tax) {
         IBillboardRegistry.Auction memory _nextAuction = registry.getAuction(tokenId_, nextAuctionId_);
 
         // skip if auction is already cleared
         if (_nextAuction.leaseEndAt != 0) {
-            return;
+            return (0, 0);
         }
 
         address _prevOwner = registry.ownerOf(tokenId_);
@@ -211,6 +223,8 @@ contract Billboard is IBillboard {
 
         // emit AuctionCleared
         registry.emitAuctionCleared(tokenId_, nextAuctionId_, _nextAuction.highestBidder, leaseStartAt, leaseEndAt);
+
+        return (_highestBid.price, _highestBid.tax);
     }
 
     /// @inheritdoc IBillboard

src/Billboard/IBillboard.sol

@@ -142,14 +142,16 @@ interface IBillboard {
      *
      * @param tokenId_ Token ID of a board.
      */
-    function clearAuction(uint256 tokenId_) external;
+    function clearAuction(uint256 tokenId_) external returns (uint256 price, uint256 tax);
 
     /**
      * @notice Clear the next auction of mutiple boards.
      *
      * @param tokenIds_ Token IDs of boards.
      */
-    function clearAuctions(uint256[] calldata tokenIds_) external;
+    function clearAuctions(
+        uint256[] calldata tokenIds_
+    ) external returns (uint256[] memory prices, uint256[] memory taxes);
 
     /**
      * @notice Place bid for the next auction of a board.

src/test/Billboard/BillboardTest.t.sol

@@ -590,15 +590,20 @@ contract BillboardTest is BillboardTestBase {
         operator.placeBid(_tokenId, _amount);
     }
 
-    function testClearAuctionIfAuctionEnded() public {
+    function testClearAuctionIfAuctionEnded(uint96 _amount) public {
+        vm.assume(_amount > 0.001 ether);
+
+        uint256 _tax = operator.calculateTax(_amount);
+        uint256 _total = _amount + _tax;
+
         (uint256 _tokenId, uint256 _prevAuctionId) = _mintBoardAndPlaceBid();
         uint64 _placedAt = uint64(block.number);
         uint64 _clearedAt = uint64(block.number) + registry.leaseTerm() + 1;
 
         // place a bid
         vm.startPrank(USER_A);
-        deal(address(usdt), USER_A, 0);
-        operator.placeBid(_tokenId, 0);
+        deal(address(usdt), USER_A, _total);
+        operator.placeBid(_tokenId, _amount);
 
         // clear auction
         vm.expectEmit(true, true, true, true);
@@ -611,7 +616,9 @@ contract BillboardTest is BillboardTestBase {
         );
 
         vm.roll(_clearedAt);
-        operator.clearAuction(_tokenId);
+        (uint256 _price1, uint256 _tax1) = operator.clearAuction(_tokenId);
+        assertEq(_price1, _amount);
+        assertEq(_tax1, _tax);
 
         // check auction
         uint256 _nextAuctionId = registry.nextBoardAuctionId(_tokenId);
@@ -624,8 +631,8 @@ contract BillboardTest is BillboardTestBase {
 
         // check bid
         IBillboardRegistry.Bid memory _bid = registry.getBid(_tokenId, _nextAuctionId, USER_A);
-        assertEq(_bid.price, 0);
-        assertEq(_bid.tax, 0);
+        assertEq(_bid.price, _amount);
+        assertEq(_bid.tax, _tax);
         assertEq(_bid.placedAt, _placedAt);
         assertEq(_bid.isWon, true);
         assertEq(_bid.isWithdrawn, false);
@@ -670,7 +677,11 @@ contract BillboardTest is BillboardTestBase {
         uint256[] memory _tokenIds = new uint256[](2);
         _tokenIds[0] = _tokenId;
         _tokenIds[1] = _tokenId2;
-        operator.clearAuctions(_tokenIds);
+        (uint256[] memory prices, uint256[] memory taxes) = operator.clearAuctions(_tokenIds);
+        assertEq(prices[0], 0);
+        assertEq(prices[1], 0);
+        assertEq(taxes[0], 0);
+        assertEq(taxes[1], 0);
 
         // check auction
         uint256 _nextAuctionId = registry.nextBoardAuctionId(_tokenId);